Apparatus and method for supplying fuel to internal combustion engines

ABSTRACT

Apparatus and method for supplying fuel to an internal combustion engine. The heated exhaust gases from the internal combustion engine are brought into direct and indirect contact with a liquid hydrocarbon fuel injected into a fuel chamber to form a mixture of vaporized liquid hydrocarbon fuel and heated exhaust gases. The mixture is passed through a passageway and further heated by non-contacting exhaust gases from the internal combustion engine to reform the mixture to hydrogen gas within the passageway for combustion in the internal combustion engine.

TECHNICAL FIELD

This invention relates to an apparatus and method for supplying fuel tointernal combustion engines. More particularly, the apparatus and methodof the invention are utilized to reform liquid hydrocarbon fuels tohydrogen gas for combustion in internal combustion engines.

BACKGROUND ART

Many arrangements are known in the prior art for cleaning the exhaust ofinternal combustion engines so that harmful materials produced duringcombustion are not emitted into the atmosphere in harmful quantities.One widely employed arrangement for accomplishing this end result is thecatalytic converter. Not only are such arrangements relatively expensiveand complex, they often require hydrocarbon liquid fuels of a precisenature or character to operate efficiently or even at all. Of course,many internal combustion engine designs require liquid hydrocarbon fuelsof a specified type to function at all, even in the absence ofassociated specialized emission control equipment.

A search directed to the present invention located the following U.S.patents: U.S. Pat. No. 5,161,365, issued Nov. 10, 1992, U.S. Pat. No.4,350,133, issued Sep. 21, 1982, U.S. Pat. No. 5,002,481, issued Mar.26, 1991, U.S. Pat. No. 4,204,401, issued May 27, 1980, U.S. Pat. No.4,802,445, issued Feb. 7, 1989, U.S. Pat. No. 4,059,076, issued Nov. 22,1977, U.S. Pat. No. 4,735,186, issued Apr. 5, 1988, U.S. Pat. No.3,736,745, issued Jun. 5, 1973, U.S. Pat. No. 4,567,857, issued Feb. 4,1986, U.S. Pat. No. 3,618,576, issued Nov. 9, 1971, U.S. Pat. No.3,896,774, issued Jul. 29, 1975, U.S. Pat. No. 3,963,000, issued Jun.15, 1976, U.S. Pat. No. 4,008,692, issued Feb. 22, 1977, U.S. Pat. No.4,041,910, issued Aug. 16, 1977, U.S. Pat. No. 4,089,314, issued May 16,1978, and U.S. Pat. No. 4,108,114 , issued Aug. 22, 1978.

Some of the aforesaid patents generally teach the concept of decomposingor reforming certain types of liquid hydrocarbon fuels to producehydrogen gas. For example, U.S. Pat. No. 4,350,133 discloses an alcoholfuel burner and decomposer in which one stream of fuel is preheated bypassing it through an electrically heated conduit to vaporize the fuel.The fuel vapor is mixed with air and the air-fuel mixture is ignited andcombusted. The combustion gases are passed in heat exchange relationshipwith a conduit carrying a stream of fuel to decompose the fuel, forminga fuel stream containing hydrogen gas for starting internal combustionengines.

U.S. Pat. No. 4,567,857 discloses an arrangement wherein methanol isdecomposed. A flow through a catalytic reactor selectively catalyticallydecomposes the methanol into a soot-free, hydrogen-rich product gas. Theengine exhaust at temperatures of 200 degrees to 650 degrees centigradeprovides the heat for vaporizing and decomposing the methanol. Thereactor is combined with either a spark ignited or compression ignitedinternal combustion engine or a gas turbine to provide a combustionengine system. The system may be fueled entirely by the hydrogen-richgas produced in the methanol decomposition reactor or the system may beoperated on mixed fuels for transient power gain and for cold start ofthe engine system. The reactor includes a decomposition zone formed by aplurality of elongated cylinders which contain a body of vapor-permeablemethanol decomposition catalyst, preferably a shift catalyst such ascopper-zinc. A vaporizer is provided for vaporizing liquid methanolprior to introduction into the elongated cylinders. Exhaust gas from theinternal combustion engine is passed in contact with the elongatedcylinders to supply the heat needed for methanol decomposition. Thepartially cooled exhaust gases are then passed to the vaporizer whereresidual heat in the exhaust is utilized in vaporization of liquidmethanol.

U.S. Pat. No. 4,735,186 discloses a method of operating an internalcombustion engine, including recycling at least a portion of the exhaustgases produced by the engine, reacting the recycled gas with ahydrocarbon fuel to produce a reformed fuel by cracking molecules of thehydrocarbon fuel. During an induction stroke an air supply is deliveredto the cylinder combustion chamber separately from a supply of thereformed fuel.

My U.S. Pat. No. 5,379,728, issued Jan. 10, 1995, discloses an apparatusand a method for supplying fuel to an internal combustion engine. Theheated exhaust gases from the internal combustion engine are broughtinto direct and indirect contact with a liquid hydrocarbon fuel tovaporize the liquid hydrocarbon fuel and form a mixture of vaporizedliquid hydrocarbon fuel and heated exhaust gases. The mixture is passedthrough a passageway and further heated by non-contacting exhaust gasesfrom the internal combustion engine to reform the mixture to hydrogengas within the passageway for combustion in the internal combustionengine.

DISCLOSURE OF INVENTION

The present invention is similar to that disclosed in my U.S. Pat. No.5,379,728 in that the present invention also relates to a method andapparatus which inexpensively, efficiently, and effectively utilizes theheated exhaust gases from an internal combustion engine to break down orreform a liquid hydrocarbon fuel to a fuel composed substantially oreven wholly of hydrogen gas for combustion in the internal combustionengine.

The invention is characterized by its relative simplicity and lowexpense. The apparatus and method of the present invention may beutilized to convert a wide variety of liquid hydrocarbon fuels toproduce a clean usable fuel with few or no pollutants.

The apparatus of the present invention is characterized by itssimplicity of construction and compactness. It requires no catalysts forits operation. The apparatus may be readily installed in associationwith virtually any type of internal combustion engine, including thoseof cars and other vehicles. Vehicles incorporating the present inventionwill have emission levels equal to or less than emissions of a newvehicle incorporating conventional smog control equipment, greatlyholding down costs.

The apparatus of the present invention is for use with an internalcombustion engine for supplying fuel to the internal combustion engine.

The apparatus includes a fuel chamber defining a fuel chamber interiorfor holding a quantity of liquid hydrocarbon fuel. Fuel injection meansis incorporated in the apparatus for injecting liquid hydrocarbon fuelinto the fuel chamber interior.

Means is provided for receiving heated exhaust gases from the internalcombustion engine for heating the fuel chamber and liquid hydrocarbonfuel in the fuel chamber interior and for substantially simultaneouslyintroducing the heated exhaust gases into the fuel chamber interior todirectly contact the heated liquid hydrocarbon fuel. This forms amixture of vaporized liquid hydrocarbon fuel and heated exhaust gaseswithin the fuel chamber interior.

Means defining a passageway is in communication with the fuel chamberinterior for receiving the mixture of vaporized liquid hydrocarbon fueland heated exhaust gases from the fuel chamber interior.

Means is operatively associated with the passageway defining means forreceiving heated exhaust gases from the internal combustion engine anddirecting the heated exhaust gases into engagement with the passagewaydefining means to heat the mixture of vaporized liquid hydrocarbon fueland heated exhaust gases in the passageway and reform at least a portionof the mixture of vaporized liquid hydrocarbon fuel and heated exhaustgases to hydrogen gas for combustion in the internal combustion engine.

The method of supplying fuel to an internal combustion engine of thepresent invention includes the step of injecting liquid hydrocarbon fuelinto a fuel chamber interior.

After the liquid hydrocarbon fuel has been injected into the fuelchamber interior, the fuel chamber and liquid hydrocarbon fuel in thefuel chamber are heated by exhaust gases from the internal combustionengine introduced into the fuel chamber interior.

The liquid hydrocarbon fuel injected into the fuel chamber interior ismixed with the heated exhaust gases introduced into the fuel chamberinterior to form a mixture of vaporized liquid hydrocarbon fuel andheated exhaust gases within the fuel chamber interior. The fuel chamberand its contents are further heated by directing heated exhaust gasesagainst the exterior of the fuel chamber.

The mixture of vaporized liquid hydrocarbon fuel and heated exhaustgases is passed through a passageway in communication with the fuelchamber interior.

The mixture of vaporized liquid hydrocarbon fuel and heated exhaustgases in the passageway is heated with heated exhaust gases from theinternal combustion engine to reform at least a portion of the mixtureof vaporized liquid hydrocarbon fuel and heated exhaust gases in thepassageway to hydrogen gas. The hydrogen gas is combusted in theinternal combustion engine.

Other features, advantages, and objects of the present invention willbecome apparent with reference to the following description andaccompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a side, elevational view of apparatus constructed inaccordance with the teachings of the present invention;

FIG. 2 is a front, elevational view of the apparatus;

FIG. 3 is a top view of the apparatus;

FIG. 4 is a sectional view taken along the line 4--4 in FIG. 3;

FIG. 5 is a sectional view taken along the line 5--5 in FIG. 3;

FIG. 6 is a cross-sectional view taken along the line 6--6 in FIG. 2;

FIG. 7 is a side, schematic view illustrating selected structuralcomponents of the apparatus and depicting flow of gases, liquids, andvapors through the apparatus;

FIG. 8 is a top, diagrammatic view illustrating selected components ofthe apparatus and depicting flow of gases, liquids, and vaporstherethrough during operation; and

FIG. 9 is a schematic diagram illustrating the apparatus of the presentinvention in combination with related structure in a representativeoperating environment.

BEST MODE FOR CARRYING OUT THE INVENTION

Referring now to FIGS. 1-8 of drawings, apparatus 10A constructed inaccordance with the teachings of the present invention includes a fuelchamber 10 defining a chamber interior 12 for holding a quantity ofliquid hydrocarbon fuel. Such fuel may, for example, comprise, amongother things, gasoline, diesel fuel, crude oil, or even used motor ortransmission oil. The present invention may be employed with a widevariety of liquid hydrocarbon fuels.

The liquid hydrocarbon fuel employed is delivered to the fuel chamberinterior 12 through any suitable conventional fuel injector meansincluding fuel injectors 16. The injected liquid hydrocarbon fuel entersthe chamber interior 12 through the bottom 20 of the fuel chamber. Thefuel chamber is also defined by a top 24 and a cylindrical wall 26between top 24 and bottom 20.

Surrounding fuel chamber 10 is a plenum 30 having ancylindrically-shaped outer wall 32. The inner wall of the plenum is thecylindrical wall 26 of fuel chamber 10. The plenum is closed by a plenumtop 36 and a plenum bottom 38.

An inlet 40 provides communication between the exhaust outlet of aninternal combustion engine (not shown) and the plenum chamber 42 of theplenum. That is, exhaust gases from the internal combustion engine arerouted through any suitable connector pipe arrangement (not shown) toinlet 40 so that the hot exhaust enters the plenum chamber 42 underpressure through inlet 40.

The heated exhaust gases circulate about the plenum, which has agenerally circular configuration, heating the fuel chamber 10 and itscontents, and exit from a plenum exit 44 to the ambient atmosphere. Thisoperation is shown in FIGS. 7 and 8 wherein arrows G are employed todepict in schematic fashion the circular path traversed by the heatedexhaust gases. A baffle plate 46 disposed within the plenum chamber 42terminates circular movement of the heated exhaust gases and assurestheir exit through plenum exit 44. Heating of the fuel chamber byexhaust gases in the plenum will contribute to vaporization of theinjected fuel therein.

At the same time that exhaust gases pass through the plenum to heat thechamber and its contents, a portion of the exhaust gases is introduceddirectly into the fuel chamber interior through an inlet port of anipple 50 projecting from and in communication with a pipe 52. That is,heated exhaust gases from the internal combustion engine circulatingabout the plenum enter the nipple and are routed through pipe 52 intofuel chamber interior 12. An adjustable needle valve 53 can be manuallymanipulated externally of outer wall 32 to control flow of exhaust gasesinto chamber interior 12 through pipe 52.

The heated exhaust gases entering chamber interior 12 through pipe 52will directly contact the injected liquid hydrocarbon fuel 14 in thefuel chamber interior. This will result in formation of a mixture ofvaporized liquid hydrocarbon fuel and heated exhaust gases. The mixturewill be displaced from the chamber interior into a passageway 60 definedby a conduit 62 having a conduit wall 64 of circular cross section and aconduit entry end 66 located above the fuel chamber bottom 20. Theconduit 62 is preferably formed from copper or other suitable materialwhich conducts heat efficiently. FIGS. 7 and 8 depict by arrows M theflow of the mixture of vaporized liquid hydrocarbon fuel and heatedexhaust gases within the chamber interior 12 and passageway 60.

The conduit 62 has a segment thereof within plenum chamber 42, thatconduit segment being spaced from the plenum walls and suspended betweenthe plenum top and bottom so that the conduit 62 is contacted by theheated exhaust gases in the plenum chamber about the entire peripherythereof.

This arrangement will result in heating of the conduit 62 by thecounter-current flow of heated exhaust gases in the plenum withconsequent further heating of the mixture of vaporized liquidhydrocarbon fuel and heated exhaust gases within the passageway 60defined by conduit 62.

Sufficient additional heating of the mixture within the confines ofpassageway 60 will cause a reaction of the mixture with resultantcombustion and reformation thereof to a hydrogenrich fuel. For such aresult to take place, the mixture within passageway 60 should be heatedto at least 300 degrees centigrade. In the arrangement illustrated,reformation of the fuel/exhaust mixture will take place at a locationwithin the passageway such as that depicted by symbol 70. The boldarrows downstream from symbol 70 depict the passage of hydrogen gasdownstream and on its way to the internal combustion engine where thehydrogen gas will be combusted.

It will be seen from the foregoing description that the method accordingto the present invention includes the step of injecting liquidhydrocarbon fuel into a fuel chamber interior.

After the liquid hydrocarbon fuel has been injected into the fuelchamber interior, the liquid hydrocarbon fuel and the fuel chamberitself are heated by exhaust gases simultaneously introduced from theinternal combustion engine into the plenum chamber and into the fuelchamber interior.

The liquid hydrocarbon fuel injected into the fuel chamber interior ismixed with the heated exhaust gases introduced into the fuel chamberinterior to form a mixture of vaporized liquid hydrocarbon fuel andheated exhaust gases within the fuel chamber interior.

The mixture of vaporized hydrocarbon fuel and heated exhaust gases ispassed through a passageway in communication with the fuel chamberinterior. The mixture of vaporized liquid hydrocarbon fuel and heatedexhaust gases in the passageway is further heated (indirectly and notthrough direct contact) by heated exhaust gases from the internalcombustion engine to reform at least a portion of the mixture ofvaporized liquid hydrocarbon fuel and heated exhaust gases in thepassageway to hydrogen gas. The hydrogen gas is then combusted in theinternal combustion engine.

FIG. 9 illustrates apparatus 10A in a typical operating environment withother structure. Since such structure is known in the internalcombustion engine and fuel injector art and forms no part of the presentinvention per se it will not be described in detail.

Suffice it to say that the structure includes a CPU. Inputs to the CPUinclude those from a crank sensor, an intake manifold pressure sensor, athrottle position sensor, an intake manifold temperature sensor and acoolant temperature sensor.

The CPU is suitably programmed so that the crank sensor input willfunction to turn the fuel injectors on and off. The function of theintake manifold pressure sensor is to regulate how long the fuelinjectors stay open. The throttle position sensor performs a similarfunction but to a somewhat lesser degree. The intake manifoldtemperature sensor and the coolant temperature sensor inputs provide forslight mixture modification.

The outputs from the CPU go to the fuel injectors through the fuelinjector drives.

The fuel pump relay is powered by a battery and provides power to thefuel pump. The relay is activated by the ignition switch. The fuel pumpis fed fuel from the fuel rail and in turn provides available pressure(e.g. 70 p.s.i.) to the fuel rail. The fuel rail then regulates the fuelsupply to the fuel injectors at a lesser pressure (e.g. 30 p.s.i.) andreturns the rest of the fuel to the fuel tank through a return hose. Thefuel injectors inject the fuel into apparatus 10A which reforms the fuelinto a clean usable fuel and supplies the reformed fuel to a fuel andair mixer which in turn supplies the correct mixture to the engine.

I claim:
 1. Apparatus for use with an internal combustion engine forsupplying fuel to said internal combustion engine, said apparatuscomprising, in combination:a fuel chamber defining a fuel chamberinterior for holding a quantity of liquid hydrocarbon fuel; fuelinjector means for injecting liquid hydrocarbon fuel into said fuelchamber interior; means for receiving heated exhaust gases from saidinternal combustion engine for heating said fuel chamber and liquidhydrocarbon fuel in said fuel chamber interior to directly contact theheated liquid hydrocarbon fuel in said liquid chamber interior to form amixture of vaporized liquid hydrocarbon fuel and heated exhaust gaseswithin said fuel chamber interior; means defining a passageway incommunication with said fuel chamber interior for receiving said mixtureof vaporized liquid hydrocarbon fuel and heated exhaust gases from saidfuel chamber interior; and means operatively associated with saidpassageway defining means for receiving heated exhaust gases from saidinternal combustion engine and directing said heated exhaust gases intoengagement with said passageway defining means to heat the mixture ofvaporized liquid hydrocarbon fuel and heated exhaust gases in thepassageway and reform at least a portion of said mixture of vaporizedliquid hydrocarbon fuel and heated exhaust gases to hydrogen gas forcombustion in said internal combustion engine.
 2. The apparatusaccording to claim 1 wherein said fuel chamber has a bottom and a topand wherein said passageway defining means comprises a conduit includinga conduit wall and a conduit entry end, said conduit entry end beinglocated above said fuel chamber bottom.
 3. The apparatus according toclaim 1 wherein said means for receiving heated exhaust gases from saidinternal combustion engine for heating said fuel chamber and liquidhydrocarbon fuel in said chamber interior includes a plenum defining aplenum chamber accommodating said heated exhaust gases, said plenumhaving a plenum inlet for the ingress of heated exhaust gases into saidplenum chamber and a plenum outlet for the egress of heated exhaustgases from said plenum chamber.
 4. The apparatus according to claim 3wherein said passageway defining means comprises a conduit having atleast a segment thereof within said plenum chamber and engaged by theheated exhaust gases in said plenum chamber.
 5. The apparatus accordingto claim 3 wherein said plenum at least partially encompasses said fuelchamber and said plenum chamber is at least partially defined by saidfuel chamber whereby said fuel chamber is engaged and heated by heatedexhaust gases in said plenum chamber to heat the liquid hydrocarbon fuelin said chamber interior and contribute to the vaporization of theliquid hydrocarbon fuel in said chamber interior.
 6. The apparatusaccording to claim 4 wherein said plenum chamber defines a substantiallycircular flow path for heated exhaust gases in said plenum chamber andwherein said conduit segment has a substantially circular configuration.7. The apparatus according to claim 6 wherein said plenum includesplenum walls defining said plenum chamber and wherein said conduitsegment is suspended within said plenum chamber and out of engagementwith said plenum walls.
 8. The apparatus according to claim 3 whereinsaid means for receiving exhaust gases from said internal combustionengine for heating said fuel chamber and liquid hydrocarbon fuel in thechamber interior includes a pipe for receiving heated, combustion gasesin said plenum and for directing the heated combustion gases receivedthereby into said chamber interior.
 9. A method of supplying fuel to aninternal combustion engine, said method comprising the stepsof:injecting liquid hydrocarbon fuel into a fuel chamber defining a fuelchamber interior so that the liquid hydrocarbon fuel occupies only aportion of said fuel chamber interior; after said liquid hydrocarbonfuel has been injected into said fuel chamber interior, heating saidfuel chamber and liquid hydrocarbon fuel in said fuel chamber withexhaust gases from said internal combustion engine while substantiallysimultaneously introducing heated exhaust gases from said internalcombustion engine into said fuel chamber interior; mixing the liquidhydrocarbon fuel injected into said fuel chamber interior with theheated exhaust gases introduced into said fuel chamber interior to forma mixture of vaporized liquid hydrocarbon fuel and heated exhaust gaseswithin the fuel chamber interior; passing the mixture of vaporizedliquid hydrocarbon fuel and heated exhaust gases through a passageway incommunication with said fuel chamber interior; heating the mixture ofvaporized liquid hydrocarbon fuel and heated exhaust gases in saidpassageway with heated exhaust gases from said internal combustionengine to reform at least a portion of said mixture of vaporized liquidhydrocarbon fuel and heated exhaust gases in said passageway to hydrogengas; and combusting said hydrogen gas in said internal combustionengine.
 10. The method according to claim 9 wherein said passageway isat least partially positioned in a plenum chamber, said heating stepincluding flowing heated exhaust gases from said internal combustionengine through said plenum chamber.